This paper discusses numerical simulation techniques for particulate flow using an efficient immersed boundary method
coupled with a new moving mesh approach. The immersed boundary method is represented by an explicit multigrid fictitious
boundary method (FBM) based on an (unstructured) FEM background grid. We compute the flow using an ALE formulation,
while the solid particles of arbitrary size and shape can move freely through the fluid. The computational mesh can be
additionally aligned by a special moving mesh method to achieve a higher accuracy near the interfaces. Numerical simulations
demonstrate the high accuracy and efficiency of the presented method.